1Caption: Kodak camera from 19212 Today, we see pictures everywhere. By just pressing a few keys on the computer or flipping through a few pages in a book we can see pictures from all over the world. But it wasn't always this way. Just a few hundred years ago, there were no such things as photographs. If we weren't able to see a person or place with our own eyes, we weren't able to see it at all.3 But the camera changed all of that. As photographs became more readily available, it became possible to see a family member who lived on another continent. It became possible to see what life was like in other parts of the world.4 The camera is the invention that made this all possible. That is why some people consider the camera one of the most important inventions of all time.5 Some cameras work by mechanical and chemical means. Others use electronic equipment to replace the chemical process. One type of camera that uses chemicals to develop its pictures is the single lens reflex, or SLR, camera. Cameras that produce their pictures electronically are known as digital cameras.